Feature Transformation – VectorIndexer (Estimator)

R/ml_feature_vector_indexer.R

ft_vector_indexer

Description

Indexing categorical feature columns in a dataset of Vector.

Usage

ft_vector_indexer( 
  x, 
  input_col = NULL, 
  output_col = NULL, 
  handle_invalid = "error", 
  max_categories = 20, 
  uid = random_string("vector_indexer_"), 
  ... 
)

Arguments

Arguments	Description
x	A `spark_connection`, `ml_pipeline`, or a `tbl_spark`.
input_col	The name of the input column.
output_col	The name of the output column.
handle_invalid	(Spark 2.1.0+) Param for how to handle invalid entries. Options are ‘skip’ (filter out rows with invalid values), ‘error’ (throw an error), or ‘keep’ (keep invalid values in a special additional bucket). Default: “error”
max_categories	Threshold for the number of values a categorical feature can take. If a feature is found to have > `max_categories` values, then it is declared continuous. Must be greater than or equal to 2. Defaults to 20.
uid	A character string used to uniquely identify the feature transformer.
…	Optional arguments; currently unused.

Details

In the case where x is a tbl_spark, the estimator fits against x

to obtain a transformer, which is then immediately used to transform x, returning a tbl_spark.

Value

The object returned depends on the class of x.

spark_connection: When x is a spark_connection, the function returns a ml_transformer, a ml_estimator, or one of their subclasses. The object contains a pointer to a Spark Transformer or Estimator object and can be used to compose Pipeline objects.
ml_pipeline: When x is a ml_pipeline, the function returns a ml_pipeline with the transformer or estimator appended to the pipeline.
tbl_spark: When x is a tbl_spark, a transformer is constructed then immediately applied to the input tbl_spark, returning a tbl_spark

Other feature transformers: ft_binarizer(), ft_bucketizer(), ft_chisq_selector(), ft_count_vectorizer(), ft_dct(), ft_elementwise_product(), ft_feature_hasher(), ft_hashing_tf(), ft_idf(), ft_imputer(), ft_index_to_string(), ft_interaction(), ft_lsh, ft_max_abs_scaler(), ft_min_max_scaler(), ft_ngram(), ft_normalizer(), ft_one_hot_encoder_estimator(), ft_one_hot_encoder(), ft_pca(), ft_polynomial_expansion(), ft_quantile_discretizer(), ft_r_formula(), ft_regex_tokenizer(), ft_robust_scaler(), ft_sql_transformer(), ft_standard_scaler(), ft_stop_words_remover(), ft_string_indexer(), ft_tokenizer(), ft_vector_assembler(), ft_vector_slicer(), ft_word2vec()